A British and a U.S. newspaper have identified a contract employee of the National Security Agency as the source of leaked information that revealed the spy agency is monitoring Americans' phone calls.

Edward Snowden, 29, says he urged The Guardian and The Washington Post to name him as their source. He tells the papers he will not hide because he insists he did nothing wrong.

Snowden, who fled the United States for Hong Kong last month, says he knows he will be made to suffer for his actions. But he said he is willing to sacrifice a "very comfortable life" to reveal the truth about what he calls a massive surveillance machine the United States is building.

He also tells the Post that he plans to ask asylum in any country he says believes in free speech and global privacy.

The Guardian reported last week that the NSA was collecting the telephone records of millions of Americans. The newspaper, along with The Washington Post, also reported that a separate program called PRISM gives the NSA and FBI access to the servers of major Internet providers.

U.S. officials do not deny the reports. They say no one listens in on anyone's telephone calls, and that the data they gathered has stopped several terrorist plots.

The U.S. Justice Department says it has opened a criminal investigation into the leaks, but has given no other information.

British Foreign Secretary William Hague says eavesdropping by its GCHQ security agency is legal and no threat to privacy. But he refuses to confirm or deny reports it received data from the secret NSA program.